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AMD RadeonSI Gallium3D Performance Has A Long Way To Go

06-28-2013, 02:12 PM

Phoronix: AMD RadeonSI Gallium3D Performance Has A Long Way To Go

With Fedora 19 presenting a nice "out of the box" experience for AMD Radeon HD 7000 series graphics using the open-source RadeonSI Gallium3D driver, benchmarks of the open-source driver were done and compared to previous generations of AMD hardware. Sadly, there's still much work ahead for the Radeon HD 7000 series driver in being able to catch up with the hardware supported under the mature R600 Gallium3D driver.

Comment

1) Llano and other AMD APUs default to a very low clock speed in the VBIOS... Could SI be doing the same?
2) All of the SI cards were using GLAMOR, while the other cards were using EXA
3) Do we know if LLVM was compiled as a debug build in this Fedora build? Debug builds of LLVM are much slower at compiling shaders
4) S3TC probably isn't enabled in this Fedora build, which probably hurts all architectures, but maybe not all are affected equally.
5) There's still lots of room for improvement in the LLVM back-end for all radeon generations
6) Was the r600g driver using llvm for shader compilation or the TGSI back-end?

The results are disappointing, yes... but how much of this is due to deficiencies in the code, and how much is due to differences in the test setup between card generations?

Comment

Sad that 2D performance was completely ignored in this benchmark round.
It would have been really interesting to see how well the completely re-done 2D driver architecture RadeonSI performs ... although I have to admit I do not have high hopes

Comment

1) Llano and other AMD APUs default to a very low clock speed in the VBIOS... Could SI be doing the same?
2) All of the SI cards were using GLAMOR, while the other cards were using EXA
3) Do we know if LLVM was compiled as a debug build in this Fedora build? Debug builds of LLVM are much slower at compiling shaders
4) S3TC probably isn't enabled in this Fedora build, which probably hurts all architectures, but maybe not all are affected equally.
5) There's still lots of room for improvement in the LLVM back-end for all radeon generations
6) Was the r600g driver using llvm for shader compilation or the TGSI back-end?

The results are disappointing, yes... but how much of this is due to deficiencies in the code, and how much is due to differences in the test setup between card generations?

About Fedora... by now, with release so close, Debug SHOULD be turned off by now unless they are waiting until the day before to recompile all the images with debugging disabled.

Comment

Sad that 2D performance was completely ignored in this benchmark round.
It would have been really interesting to see how well the completely re-done 2D driver architecture RadeonSI performs ... although I have to admit I do not have high hopes

Comment

When you do the 2D article, could you make sure to include some of the r600g cards with both EXA and GLAMOR modes? It'd help us to see how much of the performance difference is due to GLAMOR, and how much is due to the drivers.